"Man merkt die Absicht und ist verstimmt"
Content warning Slight spoiler towards the end of the paragraph
… which is Goethe and translates as "one notices the intention and is disappointed". Which is the feeling I got from reading the book: While the sections set in the early 20th century work very well, the sci-fi settings have a forced and constructed feel; while the overall story arc is makes sense, the details of the construction are visible too often (how everything is about what is real and what is virtual, about connection and loneliness, and in the end really only about the experience of Covid-19); and while the idea of using time travel as a plot device, not as the main topic, is great, there are just too many inconsistencies in how it is used (sometimes things happen the way they have always done because of some cross-time intervention, sometimes such an intervention causes things to change). Overall a nice read, but not much more.